Page:History of Richland County, Ohio.djvu/184

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��170

��HISTORY OF RICHLAXD COUNTY

��north, and the quarry is twenty feet below an opening in the same I'ock at Plymouth Village. This is the southern exposure in this neigh- borhood of unmistakable Berea, and there is great difficulty in tracing its connection with the outcrops of massive sand-rOck to the north- east, and in the central and eastern parts of the county. The surface rises to the northeast, is gently undulating, sometimes hilly, every- where exhibiting a thick deposit of drift, which conceals all the rocks, until a little north of Rome, in Blooming drove Township. On the banks of a small stream aliout fifteen feet of rocks are exposed, consisting of soft argilla- ceous shales, with haixl, Ijlue, tesselated bands which weather yellow, affording poor stone, but furuishiug the only supply in this neighborhood. These present somewhat the appearance of the Bedford shales, belonging l)elow the Berea, while, topographically, they are by the barom- eter 170 feet above the Berea last described, lu Weller Township, one-half mile northwest of ()lives])urg, awell was sunk, passing through twenty-one feet of unstratified clay drift, then striking a hard, fine-grained, blue sandstone, underlaid with alternate bands of sandstone and argillaceous shales. These were penetrated to the depth of nineteen feet, wdien a small sup- ply of water was obtained, and the explorations ceased. Four miles west, at Big Hill, the same sandstone is quarried. South of this, and in the Jiills immediately north of Windsor Sta- tion, in AVeller Township, the Waverly con- glomerate is quarried and exposed l)y outcrops and bluff's in several places. It is here 100 feet tliick. and its surface, by barometer, is 400 feet above the exposure of the Berea in Plymouth Village. It is a coarse, massive sandstone, in places white, in others covered with iron, con- taining many quartz pebbles, and presenting a strong resemblance to the ordinary conglomer- ate. In one quarry, about thirty feet of the structure of the ledge is exposed. It is mnch broken up, and, except at the top, has no reg-

��ular stratification, and is all coarse. In places it is full of pebbles, and bears little reseml>lance to any of the northern exposures of the Berea. Glacial striaj are here observed. l)earing south 32° east.

If this is a continuation of the Berea. its lithological characters here rapidly changed, and in the distance of about twenty miles it has risen about four hundred feet. This may be the fact, but, from a comparison of all the ob- servations made, it is pretty certain that it has no connection with the Berea, but is simply an ancient shore deposit of coarse material, haA- ing no great horizontal range, and not always to be found on the same vertical horizon. The Waverly rocks in passing northward liecome much more siliceous, and the sandy layers are generally composed of coarser materials. In places they consist entirel}', so far as they are exposed, of thin, fragile layers of sand}' shale, constituting the typical olive shales of the Waverly. These, in places, pass into a com- pact quarr}' rock, similar to the Logan sand- stone of Fairfield County, and often, at a dis- tance of from 120 to 250 feet below the coal- measure rocks, are succeeded by this coarse Waverl}' conglomerate. This, it is true, is about the distance below the coal measures at which the Berea is found at the north. But there is a gieat thickeuing-up southward of the Waverly rocks, and this conglomerate has neither the persistence nor any of the litholog- ical characters of the Berea. Its base, where well defined in Knox County, is shown l)y l)or- ings to be over three hundred and fift}- feet above the top of the red or chocolate shales, which there is a well-defined horizon, and ap- pears to be identical with the Cleveland shales of the Cuyahoga Valley, which are a))out seventy feet only below the Berea. These bor- ings disclose the fact that the Huron. Erie, and Cleveland shales extend northward through these counties with little change in their litho- logical characters — the Erie greatly reduced in

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